Support



y 3, 1967 K. M. GROETSCHEL 3,320,751

SUPPORT Filed Jan. 29, 1963 4 Sheets-Sheet l H 1 9 4 gi QAQL W; I 2V xvi-3' 2' INVENT OR Ker! Moria Groetschel ATTORNEYS y 23, 1967 K. M. GROETSCHEL 3,320,751

SUPPORT Filed Jan. 29, 1963 4 Sheets-Sheet 2 INVENTOR Kari Mario Groetschei ATTORNEYS y 23, 1957 K. M. GROETSCHEL 3,320,751

SUPPORT Filed Jan. 29, 1963 4 Sheets-Sheet FfiGJG. INVENTOR Karl Mario Groetsche! BYM/Z/W ATTORNEYS United States Patent O 3,320,751 SUPPORT Karl Maria Groetschel, Stolzestrasse 44, Bochum, Germany Filed Jan. 29, 1963, Ser. No. 254,713 Ciaims priority, application Germany, Jan. 29, 1962, G 34,128 37 Claims. '(Cl. 61-45) TABLE OF CONTENTS Figure Figures 11 and 12 t.

INTRODUCTION The present invention relates generally to an arrangement for supporting the roof of a mine shaft using travelling mechanical and/or hydraulic-mechanical supporting assemblies.

In the prior art devices of the type which comprise travelling supports for the roof of a mine, there is little or no provision for adjusting the support to the face or surface of the mine shaft and for compensating for changes in roof conditions. Furthermore, they are not adjustable along the entire free area of this face in dependence upon the width of the face of the working area of a mine. In known devices of the travelling type having mechanical and/or hydraulically actuated support assemblies, these features are either missing altogether or are only partially provided. In particular, the prior art arrangements have the disadvantage that a supporting effect which is exerted upon the roof in the vicinity close to the working area of the mine, is far too small to provide real protection because this area of the mine should be free of props and struts.

Accordingly, it is a main object of the present invention to provide a supporting assembly which may advance close to the working face of a mine shaft and wherein the supporting function is provided in a manner substantially more advantageous in comparison to the previously known arrangements.

Another object of the present invention is to provide a supporting device of the character described wherein an adjustment of the support of the roof of the mine shaft can be provided for various roof conditions along the entire roof area and substantially independently of the width of the Working area.

A further object of the present invention is to provide a supporting device wherein the supporting effect is provided in a forward portion of the mine in the working area thereof without the construction of props in this forward portion.

Still a further object of the invention is to provide a structure of the character described wherein a predetermined distribution of the load onto the supporting structure can he provided.

These objects and others ancillary thereto are accomplished according to preferred embodiments of the invention. In a preferred embodiment of one aspect of the present invention a supporting assembly is provided which can support the roof of the mine, close to the working area thereof. This assembly includes a forward portion and a rearward portion so arranged that a resulting supporting effect is provided which corresponds to that which would be obtained if a prop were used in the forward working area of the mine. It should be noted that as a practical matter such a prop could not 'be erected due to the necessity of providing a working front area which is free of props. This prop-free working area is necessarily inherent in practically all modern mechanical winning processes. In connection with this, a predetermined distribution of the load carried by the roof support can be I provided onto the individual props of both the forward and the rear sections.

Such a support device which provides various possibilities of adjusting to the roof conditions which are ambient in certain cases, includes a rear assembly having at least two and possibly more struts or props and a front assembly which includes a prop or strut and a cap disposed thereon. The cap is shifta-ble longitudinally and may be locked into any position into which it is moved on the prop. The cap is provided on at least one of its end portions with a pressure or load transfer element which relieves the cap from the weight of the roof in the vicinity of that portion of the cap which is supported by the prop. Such a pressure transfer element may be plate-like and mounted for turning movement in its plane in order to allow for flush contact with the roof and for the above mentioned reasons, it is arranged to be capable of being adjusted in the longitudinal direction of the cap. The caps are arranged to have such pressure transfer elements mounted on the top side or on the bottom side of the cap so that the cap of the forward assembly can be used in one position as well as in a position 180 rotated with respect thereto.

BRIEF DESCRIPTION OF THE DRAWINGS Additional objects and advantages of the present invention will become apparent upon consideration of the following description when taken in conjunction with the accompanying drawings in which:

FIGURES 1 and 2 are a schematic side elevational view and a top view respectively of a supporting assembly bracing the roof of a mine shaft.

FIGURES 3a through 3d are schematic views of cap holding bodies which may be used in the supporting assembly and FIGURE 3a is a side view and FIGURE 3b, fragmentary FIGURE 3b and FIGURE 30 are front views, while FIGURE 3d is a cross-sectional view.

FIGURE 4 is a schematic plan view of an arrangement utilizing the features of FIGURES 3.

FIGURE 5 is a schematic plan view of the bottom plate structure for the assemblies.

FIGURES 6a through are schematic views of the upper structure of the rear assembly and FIGURE 6a is a side view of one arrangement, and FIGURES 6b and 6c are front views, with FIGURE 6c showing a different arrangement thereof.

FIGURES 7a and 7b' are schematic front views illus trating another construction of the upper structure of the rear assemblies.

FIGURES 8a and 8b are a schematic plan view and a schematic side view, respectively, illustrating a further embodiment of a supporting assembly in accordance with the present invention wherein four props are used for the rear assembly, and one prop is used for the forward assembly.

FIGURES 9a and 9b are a schematic plan view and a schematic side view, respectively, of other embodiments of a supporting assembly having a rear trestle of four struts.

FIGURE 10 is a schematic plan view of still a further embodiment illustrating a rear assembly having three props.

FIGURES l1 and 12 are diagrammatic views of various load distributing arrangements using the underlying ideas of the present invention.

19 BRIEF DESCRIPTION OFTHE INVENTION The advantageous results of the present invention are accomplished inaccordance with a first embodiment or feature of the invention using support assemblies constructed in a manner known per se to have a rear assembly with at least two struts or props and a front assembly having a single prop and a cap mounted on the prop. At least one pressure transfer means or load bearing plate is provided on one end portion of the cap and by this means a substantially great portion of thesupporting effect of the prop is transferred to the end regions of the cap. This provides a corresponding decrease of the supporting effect of the cap upon the roof in the area of the cap immediately supported by the prop. The supporting effect of the prop is transferred by the cap to the pressure transfer plate and then to the roof. Also, if it is required for reasons of safety to secure the roof zone which is not at all or only to a small degree supported by the cap, additional support of the roof can be provided by means of separate support means in close proximity to the cap but independent thereof. Thus, according to thepresent invention the larger portion of the supporting effect of the cap may be provided at the forward end thereof.

A systematic change of the lever arms defined by the cap on the prop can be provided in order to differentiate the supporting effects at the two ends of the cap by local shifting of the cap on the prop and also by longitudinally adjusting the pressure transfer means mounted on the cap or by using both of these measures simultaneously. By using these steps as well as further by locally shifting the roof supporting elements of the rear assembly along the elements which carry them, the pressures of the .roof which are to be carried and the load capacities of the various supports of the entire assembly may be adjusted to all changes in the roof conditions.

In accordance with a preferred embodiment of the present invention, the cap of the forward assembly extends from the working area up to the end portion of the rear assembly disposed adjacent the mine filling so that the lever arm of the cap disposed in the rearward portion of the supporting arrangement is of substantial length. Despite the substantial dimension of the forward cap arm required because it is to extend to the immediate vicinity of the face of the working area, it is possible to maintain the lever arm relationship by means of which the major portion of the supporting eifectof the cap is on the end of the cap disposed in the working area of the shaft. Preferably the load bearing capacity of the prop which supports the cap of the forward assembly is substantially greater than that of the individual struts of the rear assembly in order to accomplish the purposes of the present invention, viz., the systematically determined distribution of the pressures which are to be borne by the total assembly.

In the supporting assemblies which follow one another in the hading direction and which are of basically the same construction, it may beparticularly advantageous to use caps of different lengths for the forward assembly and to mount these caps to have lever arms of different relationships.

In accordance with a particularly important embodiment of the invention, the forward assembly may be arranged to have two or more individual caps, ,disposedlaterally from each other. These individual caps rest upon a saddle formed in a cap holder mounted on the prop. The saddle is defined by side arms extending from the cap holder and the holder is itself seated upon the upper end of the support strut or prop. The holder itself does not touch the mine roof. This cap holder is mounted on the prop by a universal connection so as to be movable in all directions. As used in this specification and in the appended claims the term universal connection meansran arrangement whereby relative rotative motion in all directions within certain limits may take place. The caps themselves rest upon the side arms of the holder so that they are movable in all directions.

The side arms may be of equal lengths or different lengths and if desired or required, they may also be so long that each side arm can carry two adjacently disposed caps which together rest on a saddle which is pivotally mounted on :the side arm. In this latter arrangement an even more favorable distribution of the supporting effect of the forward assembly may be obtained and with a high load capacity of the forward assembly, caps of shallow profile may be used. Preferably, at least the caps of-the forward assembly are formed of box profile type members or members having a hollow space.

By using two or more caps supported by a prop in an arrangement of the type described for the forward assembly it is possible to use caps of different lengths which are carried together by the cap holder. Furthermore, the caps may be supported by means of the'side arms of the cap holder which arms are of different lengths. By this arrangement, the distance between the caps with respect to each other may be changed, and this entire ar-.

rangement may be used for obtaining a particularly wide variation of systematic supporting pressure distribution. Thus, as an example, the actual task of the forward support which is to transfer and/or withstand pressure only in its end portions may be assumed by one of the two caps carried by the arms of the holder, while a comparatively short cap resting upon the other arm of the holder may secure the section of the roof which is .not supported by the middle portion of the longer cap.

In the .latter case it may be advantageous to provide two props in the forward assembly, one for each of the two caps or cap arrangements which are to accomplish different functions. These two props are mounted on a common ground plate and each is provided with a cap holder which is suitably shaped to support the caps. In such an arrangement, the inner side arrnsof the two supporting bodies are adjacent to each other and they may be pivotally connected with each other. The joint may be provided with a saddle so that an intermediate cap can be mounted at this location.

Another feature of the invention provides a novel construction to the upper portion of the rear support assembly and is preferably a three strut unit, or even better a four strut unit, formed as a rigid frame including longitudinal caps, preferably of box profile type, and girders or traverse members connecting them. This frame, as such, may be removably mounted and locked on its struts and may be removed therefrom and displaced with respect to the struts in the longitudinal direction of the rear assembly in order to vary the regions of the roof which are immediately supported by the frame body. Preferably, saddles are formed by providing the traverse members of the frame with downwardly directed portionsfor use with the caps of the forward assembly when in their lowered position which is attained during moving of the assembly.

The longitudinal caps of the upper portion of the frame may be individual caps, but also, as explained above in connection with the cap forward assembly, may include two adjacent and connected box profile sections on each side. These longitudinal caps may support forward, and also if desired, rear cap plates connected thereto in a manner which is known per se. The forward cap plates either completely or partially secure the roof in the region of the roof which is not supported by the cap of the forward assembly.

The forward and the rear assemblies of the supporting device formed by a combination of these two assemblies, either are supported individually on a separate support, which is necessary when moving in the abovementioned single step, or they may together rest in a common substructure or bottom plate. -In accordance with a particular feature of the invention, the bottom plate is provided with a number of prop setting or supporting hole-s,

which is larger than the number of supporting props which are normally used in the assemblies. These holes are distributed in a suitable manner and may be selectively provided with props as desired. This type of arrangement allows selective systematic distribution of the load onto the individual supporting elements of the total supporting device while adjusting to changes of the roof conditions and of the side of the working area.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to supporting arrangements of the advancing type. This arrangement may include a front assembly, and a rear assembly associated therewith. The assemblies both are provided with roof supporting elements and struts or props. The roof supporting elements may be raised and lowered by raising and lowering the props. In this manner, one of the assemblies may support the roof while the other is lowered and then advanced. Then the assembly which has just advanced is moved into roof supporting position and the other assembly is lowered and advanced. Thus, the support may keep up with the advancing working area as the mining operation is carried out.

FIGURES 1 and 2 With more particular reference to the drawings, FIG- UR-ES 1 and 2 illustrate a basic embodiment of a support device wherein all of the details which are not essential for understanding the present invention are omitted. This embodiment includes a rear supporting assembly in the form of a four strut trestle 2a, and a forward supporting assembly 2. Four struts 3 are provided and they rest upon a bottom plate 4 which is provided for the rear assembly. A head frame is provided on the struts and includes two caps 5 which extend in the direction of the strike or vein, but only one of these is visible in FIG- UR-E 1. The head frame also includes traverse members 6 which are angled downwardly to form saddles. The caps 5 as well as the traverse members 6 are in the form of box profile sections or beams which, in cross section, have webs and reinforced flanges and are of the type used for certain types of caps.

The angle traverse members 6 form saddles which are provided to accommodate the cap 7 of the forward assembly. The forward assembly includes the prop 8 which is supported on a bottom plate 9', and the cap 7 is connected to the top of the prop 8. Bottom plates 4 and 9 are connected together by advancing cylinder 15. The saddles accommodate the cap 7 when the prop 8 is in its retracted position or during the moving phase of the forward assembly. As is clearly shown in FIG- URE l, the cap 7 of the forward assembly is mounted upon the prop 8 in such manner that the cap extends up to the coal K or other material which is being mined, this portion K indicating the area where the actual working of the material to be mined is being performed. A pressure transfer means or load bearing plate 9 is carried at this end of cap 7 as shown schematically in FIG- URES 1 and 2. Although this pressure transfer means or load bearing plate is not shown in all of the subsequent figures of the drawing, it may be used wherever desired and its omission is for the sake of clarity. The plate 9 is provided with a lower plug 22 which is selectively insertable into one of a plurality of holes 23 which are provided in the cap 7. Thus, the lever arms which are used for the supporting effect are adjustable as desired. The rearward portion of cap 7 extends into the rearward section of the rear assembly 2a. This long rearward section of the lever arm projects beyond the point where the cap 7 is supported by the prop 8 so that the major portion of the supporting effect of the cap '7 is effective at its forward end.

As shown in FIGURE 1, the roof of a mine shaft or tunnel is indicated at H and, as mentioned previously, the area where the coal is being worked is shown at K.

'It can be seen from this figure that although the supporting effect of the cap 7 is concentrated in the region immediately adjacent the coal working area, the cap 7 itself in the region above the prop 8, does not contact or lie against the roof. This is only one of the possibilities of the arrangement of this embodiment in a mine shaft, but it is the first one to be considered. Thus, the concept underlying the present invention is always fulfilled whenever the major portion of the supporting effect of the prop is transferred to the end regions of the cap with a corresponding decrease in the supporting effect of the cap upon the roof in the vicinity where the cap is directly supported by the prop, and this is true even if the cap contacts the roof in the vicinity where the prop supports the cap. A conveyor 24 is provided in the coal working area for use in the mining operation.

Most of the following description relates to improvements for various elements shown in FIGURES 1 and 2 and should be considered as used with the arrangement of FIGURES 1 and 2.

The cap 7 is provided with locking lugs or projections 17 known per se and which define notches which cooperate with teeth in a claw member of the prop heads 18 in such a manner that the caps are movable or shiftable on the props in their longitudinal direction and the amount of movement is determined by lengths of those regions of the caps which have the notches.

For securing the caps onto the props, the lateral edges of the prop heads 18 may be constructed to grip the flange edges of the caps as a clamp so that to move the cap, it must first be lifted until it is freed from the teeth on the prop head. Then it may be moved and once it has attained its desired position it is again inserted into the prop head teeth by lowering the cap thereon. The cap is thereby prevented from tilting laterally and the same effect is provided by these clamps if the cap is changed for another. Locking projections 17 are mounted both on the lower and on the upper sides of the caps, so that, in a known manner, it will be possible to use the cap in a reversible manner.

FIGURES 3a3d FIGURES 3a through 3d illustrate several arrangements of another embodiment wherein a cap supporting or holding device is used when the forward assembly is equipped with two or more caps disposed parallel with respect to each other. The cap holding device supports this plurality of caps.

Should two or, if desired, four caps be arranged parallel with respect to each other, an arrangement is provided which makes possible the use of caps which are of more shallow or thinner profile. In FIGURES 3a through 3d the cap holder 28 is mounted on the head or top end of the prop and is mounted so as to be universally connected to the prop head. Side arms 29 extend from the center portion of this holder in a lateral direction and in a symmetrical arrangement with respect to a longitudinal plane. These side arms define saddles for accommodating the caps 1 and 1' of the forward assembly. In order to assure that the pressure of the roof is transmitted directly to each of the caps, the saddle surfaces for the caps formed at the side arms 29, are so arrangedas determined by the dimensions of the cap profilethat they are below the upper roof contacting surface of the cap. Thus as is shown quite clearly in FIGURE 30, the upper surfaces of the caps which rest on the side arms are disposed somewhat higher than the middle portion 30 of the cap holder so that this region 30 does not itself contact the roof.

The caps rest on the side arms 29 by means of saddles 31 which are universally connected. The side arms on a holder may be of equal or of different lengths. In the modification illustrated in FIGURE 30 the side arms are so long that they each may carry two caps and one arm carries caps 1a, .1a, and the other arm carries caps lb, 1b. These sets of caps are disposed side by side. In his arrangment another. saddle or a supporting body 32 s provided which is pivotally arranged similarly to the eam of a balance. The cap holder may be universally :onnected so as to be pivotal in all directions and this is lhOWIl in FIGURE 3d. The cap holder is mounted on t regular prop head by means of a downwardly'projectng pivot pin 33 which extends downwardly into the in- :erior of the cap holder. However, as shown in FIG- URES 3a and 312 it is also possible to provide an arrangenent wherein a bushing-type saddle is formed interiorly 3f the cap holder and the prop head is fashioned in a :orresponding manner to fit into this bushing.

FIGURE 3b illustrates an arrangement wherein the side arms of adjacent cap holders can be joined together, as at 34 in FIGURE 3b. A further cap 35 could be provided at the center point between the two cap-holders. Any caps which are provided on the side arms may be secured into position by means of the locking devices provided on the saddles. Such locking devices cooperate with correspondingly constructed means disposed on the caps proper as previously described.

FIGURE 4 An arrangement is illustrated in FIGURE 4 wherein the caps 1, 1' of the forward assembly are disposed on side arms 29 of a cap holder 28 which is carried by prop 36, and this holder is of the type mentioned last above. In the illustrated embodiment, the profile caps 1, 1 of the forward assembly are connected with the caps 37, 37 extending in a longitudinal direction by means of the spring units 26, 26'- of the type illustrated in FIGURES 2a to 2d. The caps 37, 37 are portions of the upper section of the frame of the rear assembly. This assembly includes the caps 37, 37, the traverse members 38, and the struts for the rear assembly 3 9, 40, 41, and 42.

FIGURE 4 illustrates a stabilizing spring 43 which is used in this form of the invention and is fixedly mounted to the cap holder 28. This spring is connected to the cap holder and extends rearwardly therefrom and is guided in the forward traverse member 38 of the upper frame portion in a longitudinally displaceable manner. It is also possible in another arrangement to mount the stabilizing spring in a vertical plane so thatit extends from the cap holder 28 to the prop 36 in which it is displaceable in its longitudinal direction. This spring-like flexible securing of the cap holder 28 in its position is advantageous for the exchange ofthe cap carried by the cap holder as well as for the moving process.

In the embodiment illustrated in FIGURE 4, the spring unit 26 which connects one of the caps 1 of the forward assembly with the cap 37 of the rear assembly, extends for a substantial amount into the profile or interior of this cap. Also, in a manner suitable for certain roof conditions, the adjacent cap 1 is connected directly with the front end of the second cap 37 of the head frame of the rear trestle by means of the spring 26.

FIGURE FIGURE 5 is a schematic plan view illustrating the plate-like bottom structure of the rear and forward assemblies. This is an arrangement wherein the pressure distribution can be systematically changed by using the props in particular positions. The normal four strut holes 44, 45, 46, and 47, are used for a four-leg trestle in the rear assembly of a mine roof supporting device in accordancewith the present invention. Now, a further strut supporting hole 48 is formed in the bottom structure 49 of the rear assembly. Furthermore, in addition to the normal prop setting hole 50 in the bottom plate 53 of the forward assembly, additional prop setting holes 51 and 52 are disposed in a row parallel to the working front. However, if desired, the prop holes may be staggered with respect to each other. A change in the pressure distribution can be accomplished by the selective use of these" strut and prop holes. Furthermore, the forward assembly is connected with the rear trestle by means of two advancing cylinders 54. As is now clear, this construction of a bottom or sub-structure renders it possible to use a variety of combinations of struts or props both in the forward and the rear assemblies and in both assemblies together, so that the pressure distribution can be arranged as desired.

Thus, due to this construction, a choice of strut and prop arrangements is available such as one in which the rear assembly is a three-legged trestle and the forward assembly has a single supporting prop so that a total of four struts and/or props is used within the entire supporting assembly, and this type of arrangement is illustrated and described later in connection with FIGURE 10. The number of vertical supports can be increased to eight in the entire assembly, and due to this arrange-- ment advantageous as well as poor roof conditions can be taken into consideration and the supporting assembly adjusted accordingly.

FIGURES 6a-6c, 7a and 7b With more particular reference to FIGURES 6a through 66 and 7a and 7b, various arrangements are illustrated for the frame type upper portion of the rear assembly which forms a special feature of the invention. These rear assemblies can be arranged to cooperate with a forward assembly in any suitable manner, several of which are disclosed in the present specification. The caps 55, 55' extend in a longitudinal direction and form the frame-type upper structure which can be displaced, preferably as such, on the struts which carry the frame structure. These struts 57 and 58 support the caps through the use of semispherical bearings or bushing-like bodies 56, as illustrated in FIGURES 6a through 6c. These bearings 56 may be mounted by means of screws, bolts, or the like which may be inserted into holes 63, as shown in FIGURE 6a in a removable and adjustable manner at the underside as well as on the upper side of the caps 55. In addition to the capability of displacing the upper frame with respect tothe struts, this arrangement also makes it possible to use this upper section in one position as well as in a position which is rotated by with respect to the first and thus either the upper or the lower surfaces of the frame may be used to support the roof.

These holes 63 provided in the cross beam of the frame caps 55 and 55 may also be used for connecting the spring or spring units to the caps in a non-rigid manner. Such springs are to be coupled to the assembly in the forward direction. Instead of or in addition to connecting the springs these holes 63 may also be used for fastening other support elements andalso for mounting the pressure concentration plates or the like. FIGURE 6a illustrates a protective sheet 65 for protection against rockfall in the traffic path which is formed between the struts of the rear assembly which follow one another in the strike direction. This sheet 65 is flexibly mounted to the cap at 64.

FIGURES 6b and 6c are front views, wherein FIGURE 61) illustrates an arrangement of the upper frame caps 55 and 55 in one arrangement and FIGURE 6c illustrates an arrangement of caps wherein two adjacent profile members 61 and 61 are provided, with the traverse member 60 disposed therebetween. In both arrangements the traverse member 60 is not angled downwardly to form a saddle but is welded into recesses in the box profile members which are preferably used for the caps, and these profile members are provided with recessed cross pieces or stems.

FIGURES 7a and 7b illustrate front views of a preferable arrangement of the head frame wherein the caps 55 and 55' are illustrated with the traverse member 60, but the traversemembers which connect the caps are connected thereto with the use of intermediate beam members 59. FIGURE 7b illustrates the caps 62 of the forward assembly in their set or upper position and projecting in the region of the rear assembly above the traverse member 60. Only in the lowered condition of the prop of the forward assembly will the caps 62 rest upon the traverse member 60. A traverse wall 66 is provided on the traverse member 60 between the two longitudinal caps 62 of the forward assembly, and this wall defines a guide gap for these caps.

FIGURES 8a and 8]) Another embodiment is illustrated in FIGURES 8a and 8b, with 8a being a plan view and 8b a side view of a supporting device according to the present invention. A four leg or strut prop rear trestle is used and a one leg or one prop forward assembly is used. The rear trestle and the forward assembly are connected so as to be movable independently of each other, and this is accomplished by means of an advancing cylinder 67. One position of the forward assembly is shown in solid lines and another position thereof in phantom lines. Cap holding bodies 26 are used on the props 36 of the forward assembly and an upper structure arrangement is provided wherein a long cap 68 is used on one side arm 29 of the prop holder 20 and a short cap 69 is placed on the other arm 29' thereof. The roof pressure or load to be held or supported by prop 36 carrying the prop holder would be, for example, 30 tons.

In this arrangement, the pressure which the props are to support is distributed from 30 tons to tons upon each side arm of the prop holder. Of the longer cap 68, the shorter lever arm 68' thereof which extends toward the working area of the coal provides a distribution of the pressure or load due to the length relationship with respect to the lever arm 68" extending into the vicinity of the rear assembly of approximately 11 tons on the shorter arm and 4 tons on the longer arm. By correspondingly dimensioning the back arm 68" it can be assured that the forward shorter arm 68' which extends to the working area exerts the support effect according to the present invention in its end region, and it preferably carries a pressure piston (not shown). The shorter cap 69 which rests upon the other side arm 29' of the cap holding body is so mounted on the prop that the two arms which extend on both sides of the support are of equal length and thus each of the arms supports half of the total load of 15 tons. Also, as shown in FIGURES 8a and 8b, the shorter cap 69 is connected with the forward traverse member 69 of the upper frame by means of a spring unit 70.

Shown in FIGURE 8b in solid lines is the long cap in a non-supporting or lowered position after the props 36 which carry the long cap by means of the cap holder 20 have been lowered, and thus in its position before advancing the forward assembly by means of advancing cylinder 67 In this figure, the effect of the spring unit 7 0 can be clearly seen by means of which the shorter cap 69 is connected to the headframe 37, 37', 60 of the rear as sembly and also shown is the universal connection of the cap on the side arm 29' to the cap holder 20. The positions of the caps after the moving step of the forward assembly is accomplished and after the prop 36 has been extended or raised are illustrated in phantom lines.

FIGURES 8a and 8b thus illustrate how a roof zone near the free working face is supported, and thus the systematic distribution of the roof support in the zone of a support assembly: (1) in the area of the load support by the short arm 68' of the long cap 68; (2) in the area of the load support by the short cap 69' and (3) in the area at the side of the mine secured by the headframe 37, 37' and 60 of the rear assembly.

FIGURES 9a and 9b Another embodiment is illustrated in FIGURES 9a and 9b which is an improvement over the embodiment of FIGURES 8a and 8b. In this embodiment in addition to the single supporting prop 36 of the forward assembly, there are, on both sides of the prop 36, further props 71 and 72 which carry short caps 73 to secure the areas on both sides of the long caps 68 at those places where caps 68 do not themselves provide a supporting effect. The caps 68 which are part of the forward assembly are of equal length and are arranged to carry out equal supporting functions. The forward ends of the caps 68 are provided with pressure discs 21 or with similarly effective universally connected short caps or profile members 74 which can be placed laterially onto these ends, and all of these are pressure transfer or supporting means. Thus, an assembly is provided which has seven struts and props. If desired, the rear assembly can be provided with a further strut using one of the strut holes provided for this purpose by means of indentations in the bottom plate of the assembly and thus providing a total assembly of eight legs or props.

Due to the length relationships which are provided in the embodiment for the two arms of the caps 68 about 70% of the supporting effect of the center support of the forward assembly is shifted into the immediate region of the working area and the remainder of about 30% is moved into the hind trestle zone. The middle or intermediate roof portion which is not influenced by the prop 36 of the forward assembly is fully supported by the two lateral props 71 and 72.

FIGURE 9b more clearly shows an arrangement for use when roof conditions are more favorable and members 73 are pivotally connected to section 37 of the headframe of the rear assembly and they may, themselves or by means of caps 73 which may be located at their front ends, press against the roof, in a manner which is known per se by means of a preferably hydraulic-actuated device 75, 76. The caps press against the roof in which case, particularly when favorable roof conditions prevail, the props usually carrying these caps, which are props 71 and 72, may be omitted.

FIGURE 10 With more particular reference to FIGURE 10, an arrangement which has been mentioned above is illustrated wherein the rear assembly is a three-legged or three strut trestle, having three struts 77, 78 and 79, and which is generally T-shaped in plan view. The beam 80 of this T-shaped arrangement forms the headframe and extends to the working area side of prop 77. This beam may carry a pressure transfer plate 21 which is movable in a horizontal plane. In this arrangement, the forward assembly includes two long caps 81, 81', and props 82, 82', respectively, each of which is associated with and carries one of the caps. The front lever arms of these long caps carry the pressure transfer elements 21 and the front arms are also of the same length. The rear arms may also be of equal length, as illustrated. In accordance with an other arrangement which, at times, may be more suitable, the rearward arm of one of the two long caps 81, 81', is longer than that of the other long cap so that the one cap which is longer transfers, via its shorter arm and the pressure transfer means 21 carried thereby, a greater por tion of the supporting effect of its prop than the shorter cap. The two props 82, 82' of the forward assembly are supported upon the bottom plate illustrated in FIGURE 5 and in this plate, the third of the prop holes provided therein is still unoccupied, and, if desired, it may be filled by a further prop 83. This prop may then carry a forward cap plate 84 which secures the middle section between the two props 82 and 82', that is, the region in which these caps are not directly effective.

A transfer beam 85 extends from the beam 80 of the rear trestle and has side arms which form saddles for the caps 81, 81' in the lower condition of these caps in a manner which is equivalent to that of the downwardly angled traverse member 60, for example those illustrated in FIGURE 7.

The support assembly according to the present invention renders it possible to use any means whatsoever for moving the assembly, that is, this process can al ways be accomplished while the roof is protected. In supporting assemblies of the type similar to the present invention either the forward and rear assemblies are moved together or they are moved separately or individually. A particular feature of the present invention provides a construction wherein the forward assembly and the rear trestle are connected by means of a mechanical or hydraulic one or multi-cylinder advancing device instead of the pivotal connection or splicing plate connection or the like usually used in the known arrangements. This advancing device is effective at the rear trestle but is capable of being inactivated so that by this arrangement two types of advancing arrangements may be provided. In one arrangement when the roof is in a good condition, the advancing device may be suitably activated so that the forward and rear assemblies move together or, in the case of a bad roof, the two assemblies may be moved in a dragging step with first one advancing and then the other in a suitable manner so as to protect the roof.

FIGURES 11 and 12 FIGURES 11 and 12 are diagrammatic views schematically illustrating the various arrangements of the present invention in accordance with the foregoing figures assuming the load on a sole prop to be 30 tons. FIGURE 11 illustrates the systematic distribution of the supporting effect of the forward assembly and this distribution is provided by the various combinations for arranging and constructing the upper parts carried by the prop of the novel supporting device. The prop position is indicated by the small circle. The numerals in the various schematic figures list the portions of the load distributed ontothe individual support or load regions in tons. The numerals to the left of the schematic views number the possibilities which are illustrated. The illustrations 1 to 4 illustrate the arrangement wherein a single cap is used. The different loads at the two ends of the cap of the forward as sembly which are effective through the single prop of the cap in accordance with the support location of the cap are designated. In the illustrations 5 through other possibilities are shown, when a double cap system is used for the forward assembly and wherein the two caps are movable independently of each other. Further, it is shown that the holder side arms may be of different lengths. FIGURE 12 schematically illustrates an arrangement wherein certain features are combined along particular portions of the mine face to provide a systematic distribution of the entire free roof area into zones and regions of certain and predetermined load capacities.

It should be clear that the present invention is not limited to the specific embodiments described and illustrated and is not limited to either the simultaneous or combined application of all of the features, but rather individual features thereof may even be combined with other support assemblies, since this is within the scope of the basic idea of the present invention.

It will be understood that the above description of present invention is susceptible to various modifications, changes, and adaptations, and the same are intended to be comprehended within the meaning and range of equivalents of the appended claims.

What is claimed is:

1. An advancing mine supporting arrangement for bracing the roof of a mine, comprising, in combination:

(a) a rear assembly having at least two struts;

(b) a forward assembly associated therewith and having only one prop and a cap thereon defining a lever having a longer and a shorter lever arm, said cap extending rearwardly past the forward-most portion of the rear assembly; and

the

(0) load transfer means positioned on and extending upwardly from at least one end portion of said cap and supported on at least said shorter lever arm of the cap for transferring to the end portion of the cap at least the major portion of the supporting effect of the prop, for correspondingly decreasing the supporting effect of the cap upon the roof in the vicinity where the prop supports the cap and for engaging the longer lever arm against the roof.

2. An arrangement as defined in claim 1 comprising separate supporting means on said rear assembly in close proximity to and independent of said cap for supporting the roof region supported to a smaller extent by said cap.

3. An arrangement as defined in claim 1 wherein said load transfer means are at least disposed on the forwardmost lever arm of said cap which isnear the coal face.

4. An arrangement as defined in claim 1 wherein said load transfer means is mounted for selective positioning 1 along said cap whereby the supporting effect thereon may be varied.

5. An arrangement as defined in claim 3 wherein said cap extends from the coal facearea to the end region of the rear assembly and said longer lever arm is sufficiently long that even though said shorter lever arm extends forwardly for a substantial distance the lever arm a relationship by which the major portion of the supporting effect is transferred to the end of the cap at the coal face area is maintained.

6. An arrangement as defined in claim 1 wherein said prop is stronger than and thus capable of withstanding a greater load than the struts of the rear assembly.

7. An arrangement as defined in claim 1 wherein two caps arranged parallel to each other and laterally spaced and supported by the prop provide the supporting effect for the forward assembly.

8. An arrangement as defined in claim 1 wherein said load transfer means are plate-like bodies and comprising means for mounting such bodies for turning.

9. An arrangement as defined in claim 1 wherein said cap is arranged to accommodate said load transfer means on both sidesthereof.

10. An arrangement as defined in claim 1 wherein said cap includes two parallel cap elements mounted on said prop of said forward assembly.

11. An advancing mine supporting arrangement for bracing the roof of a mine, comprising, in combination:

(a) a rear assembly having at least two struts;

(b) a forward assembly connected therewith and having ( a p p (2) two parallel caps having removably lockable means on different portions along the caps for removably locking the caps to the prop and each cap defining a lever having arms, and

(3) a cap holder disposed on the upper end of said prop and universally movable with respect thereto, the uppermost surface of said cap holder being disposed below the upper surfaces of the caps so that the cap holder will not lie against the roof, said cap holder having two arms, one extending from each side thereof to define saddles in which the caps rest; and

(c) load transfer means positioned above the upper plane of the caps and disposed on at least one end portion of a cap and supported on one lever arm of such cap for transferring to the end portion of such cap at least the major portion of the supporting effect of the prop and for correspondingly decreasing the supporting effect of such cap upon the roof in the vicinity where the prop supports such cap.

12.. An arrangement as defined in claim 11 wherein said arms extending from both sides of said holder are of equal lengths.

13. An arrangement asdefined in claim 11 wherein said capholder includes vertically mounted middle sections onto which said side arms are mounted, said middle sections being disposed close to said prop 14. An arrangement as defined in claim 11 wherein said cap holder includes intermediate members mounted on the saddles for universal movement and on which the cap actually is mounted.

15. An arrangement as defined in claim 11 wherein said side arms forming the saddles are of different lengths and said caps carried thereby thus project for different distances from the center axis of the prop of the forward assembly.

16. An arrangement as defined in claim 15 wherein the cap on the forward assembly which extends into the region close to the working area is mounted on one saddle and the cap mounted on the other saddle is shorter to support the region of the roof which is not supported by the first-mentioned cap.

17. An arrangement as defined in claim 11 wherein said side arms defining the saddles and extending laterally of said cap holder are of sufficient length to accommodate two caps in a side-by-side arrangement, said cap holder including a supporting body pivoted to the saddles in scale beam balance fashion to support two side-by-side caps, and a supporting saddle for each cap mounted two on each supporting body and in a universally pivotal fashion.

18. An arrangement as defined in claim 11 wherein said forward assembly includes at least two props and two cap holders, said holders having arms facing each other, and means pivotally connecting the ends of the facing saddle arms.

19. An arrangement as defined in claim 18 comprising a further cap mounted between the two cap holders.

20. An advancing mine supporting arrangement for bracing the working area of a mine, comprising, in combination:

(a) a rear assembly having at least two struts;

(b) a forward assembly connected therewith and having ( l) a prop,

(2) a cap mounted on said prop and defining a lever having at least two lever arms of different lengths, and

(3) locking means for detachably connecting said cap to said prop for removably locking different portions of said cap onto said prop so as to vary the lengths of and the relationship between the respective lever arms thereof; and

(c) load transfer means positioned on and disposed above at least one end portion of said cap and supported on the shorter of said lever arms of said cap for transferring to an end portion of the cap at least the major portion of the supporting effect of the prop and for correspondingly decreasing the supporting effect of the cap upon the roof in the vicinity where the prop supports the cap,

21. An arrangement as defined in claim 20 comprising a cap holder universally connected to the upper end of said prop and having two side arms, one projecting from each side thereof to define two saddles for accommodating two caps, said cap holder being connected with the rear assembly by at least one flexible intermediate element.

22. An arrangement as defined in claim 20 wherein said assemblies include a bottom structure provided with a plurality of prop and strut setting holes which is larger in number than the number of struts and props to be used, said holes being distributed over said bottom structure and being filled selectively with props and struts having a supporting capacity which is chosen as desired, the arrangement of holes being such that the supporting capacity of the props may be different depending upon the arrangement of props and struts placed into said holes.

23. An arrangement as defined in claim 20 wherein the upper portion of said rear assembly includes a frame of longitudinal caps of box profile form and traverse members connecting said caps.

24. An arrangement as defined in claim 23 wherein said traverse members are bent downwardly in the middle sections thereof to define a saddle and said forward assembly has a long cap, the rearward portion of which extends above said traverse members in its roof-supporting position, and is supported by said traverse members in the lower position of said cap.

25. An arrangement as defined in claim 23 wherein said frame includes two adjacently positioned box profile form caps on each side.

26. An arrangement as defined in claim 23 wherein said rear assembly includes at least one cap breast plate mounted at one end of the longitudinal caps of said frame.

27. An arrangement as defined in claim 20 wherein said assemblies include a bottom structure provided with a plurality of prop and strut setting holes which is as large in number as the largest number of struts and props to be used and which is thus greater than the normal number of props and struts to be used, said holes being distributed over said bottom structure and being filled selectively with props and struts having a supporting capacity which is chosen as desired, the arrangement of holes being such that the supporting capacity of the props may be different depending upon the arrangement of props and struts placed into said holes, the upper portion of said rear assembly includes a frame of longitudinal caps of box profile form and traverse members connecting said caps, at least one additional prop being arranged in the bottom plate of said forward assembly in addition to the prop carrying the cap thereof, at least one short additional cap disposed on said additional prop and connected to the upper portion of said frame for supporting the region of said roof which is not supported by the cap of the forward assembly.

28. An arrangement as defined in claim 27 wherein said additional cap of said forward assembly is coupled with the cap of the upper portion of said rear assembly, and hydraulic means braced at the rear assembly for pressing said additional cap against the roof.

29. An arrangement as defined in claim 20 wherein said forward assembly includes a plurality of caps disposed in parallel arrangement, a plurality of props for supporting said caps, a cap holder disposed on each prop and arranged to carry two caps, one on each side thereof.

30. An arrangement as defined in claim 29 wherein two long caps are provided in the forward assembly and an additional cap is provided between the two long caps.

31. An arrangement as defined in claim 30 wherein said rear assembly is provided with three struts and has an upper portion in the form of a T-shaped frame having a longitudinal beam extending at the side of the working area and provided with a pressure disc for absorbing at least part of the load to be supported in the zone which is not supported by said long caps which are arranged on both sides of said longitudinal beam, and laterally extending bearing arms projecting from said longitudinal beam, and disposed in a position which supports said long caps when they are in their lowered condition.

32. In an advancing mine supporting arrangement for bracing the working area of a mine which comprises a rear assembly having at least two struts, a forward assembly associated therewith having a prop, a cap mounted thereon and defining a lever having arms, and locking means detachably connecting the cap to the prop for removably locking different portions of the cap onto the prop so as to vary the lengths of the respective lever arms thereof, and load transfer means on at least one end portion of the cap and supported on one lever arm of the cap for transferring to the end portion of the cap at least the major portion of the supporting effect of the prop and for correspondingly decreasing the supporting effect of the cap upon the roof in the vicinity where the prop supports the cap, the improvement wherein said locking means includes a plurality of notches defined in a flange on said cap, and a member on the upper end of said prop and having teeth to define a claw with the teeth thereof positioned apart a distance equal to the distance between notches on said flange so that said cap may be placed onto said claw with the teeth thereof projecting into said notches, said teeth being disposed on both sides of said cap and said notches being larger in longitudinal direction than said teeth by an amount which allows the cap to be inclined by a small angle on the prop but prevents it from entirely tipping ofi the prop whereby the prop may be lifted above said teeth and its position shifted longitudinally and another portion having notches may be lowered onto said teeth so that the position of said cap on said prop may be changed.

33. A support comprising a prop, a cap having a flange mounted thereon, and locking means mounting said cap on said prop, said locking means including a plurality of notches defined in a flange on said cap, a member on the upper end of said prop and having teeth to define a claw with the teeth thereof positioned apart a distance equal to the distances between notches on said fiange so that said cap may be placed onto said claw with the teeth thereof projecting into said notches, said teeth being disposed on both sides of said cap and said notches being lar-gerin longitudinal direction than said teeth by an amount which allows the cap to be inclined by a small angle on the pro but prevents it from entirely tipping off the prop whereby the prop may be lifted above said teeth and its position shifted longitudinally and another portion having notches may be lowered onto said teeth so that the position of said cap on said prop may be changed, and a cap holder disposed on the upper end of said prop and universally movable with respect thereto, the uppermost surface of said cap holder being disposed below the upper Surface of the cap, said cap holder having two arms one extend ing from each side thereof to define saddles in which caps may rest,

34. A support as defined in claim 33 wherein said cap holder includes intermediate members mounted on the saddles for universal movement and on which caps may actually be mounted.

35. In a mine support arrangement having a forward assembly with a long cap and a rear assembly, the improvement comprising an upper section for the rear assembly including a frame of longitudinal caps of box profile form with thickened bottom flanges and thinner inwardly displaced webs, and traverse members connect ing said caps and being angled downwardly to define a saddle and the rearward portion of the cap of the forward assembly extending above said traverse members in its roof supporting position, and being supported by said traverse members when the cap is in a lower position thereof.

15 36. An advancing mine supporting arrangement for bracing the coal face area of a mine, comprising, in combination:

(a) a forward assembly associated therewith and having one prop and a cap thereon defining a lever having a longer and a shorterlever arm;

(b) load transfer means positioned on and disposed above at least one end portion of said cap and supported on at least said shorter lever arm ofthe cap for transferring to the end portion of the cap at least the major portion of the supporting eifectof the forward assembly prop and for correspondingly decreasing the supporting effect of the cap upon the roof in the vicinity where the forward assembly prop supports the cap; and (c) a rear assembly having a first and at least one second prop, a beam supported by said first prop and not contacting the roof in the area where the beam is supported by said first prop, pressure transferring means arranged at least at one end of the beam, said second prop supporting the other end of said beam. 37. An arrangement as defined in claim 25 wherein said frame is mounted to be displaceable and to be capable of being locked to the arrangement in the longitudinal direction thereof.

References Cited by the Examiner UNITED STATES PATENTS 3,097,829 7/1963 Seddon 61-45.2 3,169,377 2/1965 Hoffman 6145.2

FOREIGN PATENTS 569,133 Belgium. 1,201,150 1959 France. 1,251,175 1960 France. 1,272,244 1961 France.

704,338 1954 Great Britain. 706,002 3/1954 Great Britain. 83 0,704 3 1960 Great Britain. 845,302 8/1960 Great Britain. 854,967 11/1960 Great Britain. 858,633 l/1961 Great Britain. 865,922 4/ 1961 Great Britain. 885,645 12/1961 Great Britain.

OTHER REFERENCES Das. 1,077,619, German application to Reieinstahl.

CHARLES E, OCONNELL, Primary Examiner.

EARL J. WITMER, JACOB L. NACKENOFF, JACOB SHAPIRO, Examiners. R. A. STENZEL, Assistant Examiner. 

1. AN ADVANCING MINE SUPPORTING ARRANGEMENT FOR BRACING THE ROOF OF A MINE, COMPRISING, IN COMBINATION: (A) A REAR ASSEMBLY HAVING AT LEAST TWO STRUTS; (B) A FORWARD ASSEMBLY ASSOCIATED THEREWITH AND HAVING ONLY ONE PROP AND A CAP THEREON DEFINING A LEVER HAVING A LONGER AND A SHORTER LEVER ARM, SAID CAP EXTENDING REARWARDLY PAST THE FORWARD-MOST PORTION OF THE REAR ASSEMBLY; AND (C) LOAD TRANSFER MEANS POSITIONED ON AND EXTENDING UPWARDLY FROM AT LEAST ONE END PORTION OF SAID CAP AND SUPPORTED ON AT LEAST SAID SHORTER LEVER ARM OF THE CAP FOR TRANSFERRING TO THE END PORTION OF THE CAP AT LEAST THE MAJOR PORTION OF THE SUPPORTING EFFECT OF THE PROP, FOR CORRESPONDINGLY DECREASING THE SUPPORTING EFFECT OF THE CAP UPON THE ROOF IN THE VICINITY WHERE THE PROP SUPPORTS THE CAM AND FOR ENGAGING THE LONGER LEVER ARM AGAINST THE ROOF. 